1. Field of the Invention
The present invention relates to an electronic appliance, and particularly, to an electronic appliance having a display, such as a television set and a personal computer, provided with an improved remote control function.
2. Description of Related Art
In the 1980s, infrared remote controllers started to be attached to home appliances such as television sets. The remote controllers have widely accepted and greatly changed the usage of home appliances. At present, controlling electronic appliances with the remote controllers is in the mainstream. The remote controller basically employs a one-key (one-button), one-function operation. A remote controller for the television set, for example, has ON/OFF, CHANNEL, VOLUME, and INPUT SELECT keys for conducting respective functions. The remote controller is very useful for remotely controlling the television set and electronic devices connected to the television set.
Data broadcasting that has started recently requires a remote controller to be provided with UP, DOWN, LEFT, RIGHT, and OK keys, and the user must push these keys several times to display a necessary menu. This is troublesome for the user. An EPG (electronic program guide) displays a matrix of guides and prompts the user to select a desired one of the guides by pushing keys on the remote controller. This is also troublesome for the user.
A related art proposed by this applicant in Japanese Unexamined Patent Application Publication No. 2006-091948 discloses a remote-control technique that uses no remote controller at hand and is flexibly applicable to a variety of electronic apparatuses. This technique employs a video camera to photograph the hand of a user moved with respect to a control button displayed on a display, and according to the hand's movement, identifies a control operation assigned to the control button.
This related art is capable of correctly detecting a hand motion of the user carried out with respect to a control button displayed on a display. The related art, however, is not good at detecting a hand motion when a background color of the hand photographed by the video camera is similar to the color of the hand itself. There is, therefore, a need for providing a technique to correctly detect a control button manipulating operation conducted by a subject (hand) even if a background color of the subject is similar to the color of the subject itself.